WEDNESDAY, April 19 (HealthDay News) -- There's no conclusive evidence to indicate which approach -- mouthwash, breath mint, spray, chewing gum or mechanical tongue cleaning -- is most effective for treating bad breath (halitosis), says a new review of previous clinical studies.

"From the results of some low-powered trials, tongue cleaning, scraping and brushing do appear to have some benefit at reducing halitosis, and the effects appear to be short-lived," review co-investigator Zbys Fedorowicz, a periodontist at the Ministry of Health in Bahrain, said in a prepared statement. "But we were unable to find any reliable evidence confirming any benefits of using tongue-scraping over mouthwash, or vice-versa, at reducing halitosis."

Halitosis is caused by accumulated bacteria and the decay of food particles and other debris in the mouth.

Currently, there are no standard and accepted methods for treating halitosis. Mouthwashes, sprays, mints and gums provide a competing and temporary smell that masks bad breath. Some mouth rinses have ingredients that neutralize the odor or the bacteria that produce it.

Tongue brushing and scraping dislodge trapped food and bacteria, which can also be reduced by improving oral hygiene.

The findings appear in the latest issue of the journal The Cochrane Library.

More information

The American Dental Association has more about halitosis.